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BRANCH COUNTY
BRONSON
Congressional District # 07
NORTH BRONSON INDUSTRIAL AREA
EPA ID# MID005480900Last Updated: July, 2008
Site Description
The North Bronson Industrial Area (NBIA) site, located in Branch County, Bronson, Michigan, consists of two lagoon areas and a county drain which runs adjacent to the lagoons. Several industries in the area discharged plating and other industrial wastes to seepage lagoons between 1939 and 1981. An industrial sewer system was used to transport plating wastes to both sets of lagoons, which were owned and maintained by the city of Bronson. The seepage lagoons are no longer used for waste disposal; however, they contain an estimated 130,000 cubic yards of heavy metal sludges.
The majority of the city of Bronson is within a one-mile radius of the old lagoons at the NBIA site. The area surrounding the site is mixed industrial and residential; north of the site is primarily rural. The majority of the residents in the area of the site are connected to the municipal water supply system, though an estimated 3,000 people within three miles of the site use wells as a source of drinking water. The primary supply wells are located approximately 5,000 feet west of the site and are screened in the upper aquifer.
Site Responsibility
This site is being addressed through federal and state actions.Threats and Contaminants
High levels of trichloroethylene, dichloroethylene, and vinyl chloride (also known as volatile organic compounds or VOCs) as well as elevated levels of heavy metals and cyanide, have been detected in private and groundwater monitoring wells in the area. Polychlorinated biphenyls (PCBs)and metals such as cadmium have been found in sediment samples downstream of the old lagoons. Lagoon sludge contains heavy metals, including cadmium, chromium, and lead. Municipal wells are located upgradient of the site with only a remote chance of site contaminants reaching these wells. Accidental ingestion of or direct contact with, the contaminated groundwater, sediment, and sludge could pose a health threat to people.Cleanup Progress
In 1988, action was taken to eliminate immediate threats by removing from service private wells found to be contaminated with metals and VOCs. Alternate water supplies were provided to the affected residences. In 1993 and 1994, United States Environmental Protection Agency (U.S. EPA) Technical Assessment Teams were dispatched to the site. During the 1993 visit, the site was evaluated for immediate threats to human health. In several of the remaining buildings, waste piles, vats and drums were identified, characterized and secured. In 1994, the vats were pumped clean, and the drums were overpacked and removed from the site. The vats were covered and the buildings were secured to prevent trespassing.
The Remedial Investigation and Feasibility Study (RI/FS) was conducted under State Lead-Fund Financed activities. Cleanup options to address the lagoons and the drain (Operable Unit 1; OU1) were evaluated and a decision on the final cleanup remedy was made in June 1998 in a Record of Decision (ROD) signed by the Michigan Department of Environmental Quality (MDEQ) and U.S. EPA. The selected remedy is to consolidate contaminated soils into one area of the western lagoons, dredge sediments from the County Drain #30 and consolidate them in that area as well, and to construct a Wetland to treat groundwater from the lagoon area.
Remedial Design and Remedial Action (RD/RA) negotiations with potentially responsible parties (PRPs) began a week after the ROD was signed. A Consent Decree (CD) was signed by U.S. EPA and the five PRPs. RD began in February 2000, with the first task being Pre-Design Studies (PDS). Field Work for PDS took place between February 2001 and March 2001, including the installation of new monitoring wells, abandonment of wells, sampling sediment and development of new wells.
The Draft PDS Report was submitted in July 2001 for U.S. EPA and MDEQ review and comment. The revised report was submitted on November 5, 2001 and did not meet the requirements of the Statement of Work and CD. Per a request from U.S. EPA, the Draft Phase II PDS Work Plan was submitted on May 20, 2002, which included additional field studies north and south of the County drain #30. The final Phase II PDS Work Plan was submitted in July, 2002. Field work took place in August 2002. EPA received the Draft Phase II PDS Technical Memorandum in December 2002. Work conducted as part of the PDS showed possible problems with the implementation of the constructed wetland approach for groundwater treatment. Pending resolution of implementation issues with the ROD-selected groundwater treatment approach, the PRPs have proposed to enhance the source control portion of the lagoon closure remedy by adding solidification and stabilization additives. This will give the lagoon sludges the strength necessary to support a cover and should reduce leaching of contaminants to groundwater. In 2006, the PRPs are evaluated solidification and stabilization mixes and conducted a pilot scale field test of mixtures. An Explanation of Significant Differences (ESD) document was issued in September 2008 that clarifies the cleanup requirements and documents that the use of stabilization and solidification is acceptable in conjunction with lagoon closure activities. Any modification to the original groundwater remedy selected in the ROD will be addressed though a future ROD amendment.
Operable Unit 2 (OU2) consists of the Industrial Sewer that was used by the industries to transport their liquid wastes to the waste lagoons. MDEQ began investigations of the sewer in September 1996 and subsequently sampled again in May 1998. Results of these two sampling activities are reported in Technical Memorandums for the Industrial Sewer. U.S. EPA began negotiations with the PRPs in September 2000, for the FS. As a result of these Negotiations, U.S. EPA and the PRPs agreed to evaluate upstream source areas "abandoned facilities" prior to completing work on Industrial sewer.
North Bronson Former Facilities - The upstream sources that were identified as part of discussion for OU2 were evaluated by EPA and PRPs. Work on these sources is proceeding. These facilities are known as the North Bronson Former Facilities and include the former Bronson Reel facility, the former L.A. Darling facility, and the former Scott Fetzer facility.
* Former Bronson Reel Facility - A Record of Decision (ROD) was issued for the former Bronson Reel facility on September 26, 2006. The ROD requires: (1) the implementation of a warranty deed restriction on the property to require follow-up sampling under the site buildings if the foundations are ever removed, and (2) the implementation of groundwater use restrictions because of concerns about site-wide groundwater contamination that impacts the northern industrial area of Bronson. No other risks from the source area were identified.
* Former L.A. Darling Facility - The former L.A. Darling facility contains metal and solvent contamination in its soil and groundwater. The site PRP completed the RI Report in 2006 and submitted a draft FS for EPA review in the Fall of 2006. The PRP revised the FS based on EPA and Michigan DEQ comments. In the fall of 2007, L.A. Darling commenced a partial removal of contaminated soil from the property to allow for the construction of a road though part of the property. In a Record of Decision issued in September 2008, EPA selected a cleanup approach for the facility. The cleanup plan requires excavation of contaminated soils above the water table and institutional controls to ensure continued commercial/industrial use of the property. The ROD selected an interim action for groundwater, with the selection of Air Sparging and Soil Vapor Extraction (SVE) to remove volatile organic contaminants. When the efficiency of the Air Sparge / SVE system slows and it is no longer removing sufficient levels of VOCs from the groundwater and saturated soils, the system will be converted to a extract and treat groundwater. This two-pronged approach, with Air Sparge / SVE and then “pump and treat”, should dramatically reduce VOC concentrations at the facility. This groundwater approach is an interim remedy because it is not meant to address the entire contaminant plume from the former L.A. Darling facility. Groundwater contamination from L.A. Darling overlaps with contamination from other sources. A cleanup plan to address combined plume areas will be issued as a separate decision document.
* Former Scott Fetzer Facility - - The former Scott Fetzer facility also contains metal and solvent contamination in its soil and groundwater. The final RI report ihas been completed and a final FS is under review and is expected to be completed summer 2009. A ROD is expected in 2009.
Groundwater contamination from the former L.A. Darling facility and the former Scott Fetzer facility extends under a residential area in the north of Bronson. Because the U.S. EPA was concerned that the high VOC levels in the shallow groundwater could pose a threat to the indoor air of nearby residents, the U.S. EPA required the site PRPs to implement a soil gas monitoring program. Soil gas samples have been routinely collected from yards near the facilities and public right-of-ways. In areas where the soil gas samples showed elevated levels of VOC vapor, indoor air samples were collected from homes where vapor intrusion could be problematic. To date, four homes near the facilities have been found to contain VOC vapors above indoor air action levels. EPA and the PRPs are working with the homeowners to install and test venting systems to eliminate potential impacts to indoor air.
Contacts
Remedial Project Manager, U.S. EPAjames hahnenberg (hahnenberg.james@epa.gov)
(312) 353-4213
Community Involvement Coordinator, U.S. EPA
dave novak
(312) 886-7478
Aliases
NORTH BRONSON IND AREABRONSON RESIDENTS WELL
BRONSON PLATING MFG CO
BRONSON PLATING CO
BRONSON WWTP